It was the pain in Ken Witty's legs that upset his 36-year tennis rivalry with pal Peter Wolf. "I did physical therapy for a number of months, and that didn't work," Witty says. "And then, I had a cortisone shot in the back, and that worked for a few weeks." But the pain came back even worse, settling on the then 70-year-old's right ankle. "It got to the point where I could stand in the middle of the court, but if I had to run to either side, it just killed," he says. Witty's discomfort was the result of a common aging condition called lumbar spinal stenosis. His doctor, Mount Sinai spinal surgeon Sheeraz Qureshi, MD, says that Witty's symptoms, which can appear in those in their 50s and 60s, may have even been delayed because he's in such good shape. "In Ken's case, unfortunately, regardless of how strong his muscles were, he was going to have symptoms going down his legs because the nerves just didn't have enough room to be able to function appropriately," Dr. Qureshi says. Learn more